Conventionally, the package structure for a CCD or CMOS image sensor takes a system that to protect a sensor section from foreign matter such as water and dust, the sensor section is bonded to a protective glass with a liquid or film-form, photocurable photosensitive resin composition applied by a printing method such as dispensing. The application of such an adhesive by a photolithographic method first includes coating a photosensitive adhesive composition or laminating a photosensitive adhesive film on a silicon substrate or glass substrate to form a photosensitive adhesive layer. After the photosensitive adhesive layer is next subjected to exposure, baking and development, a protective glass substrate (silicon substrate) is brought into close contact with the resulting adhesive layer, followed by pressing under heat to bond the adhesive layer and the protective glass substrate together. Subsequently, heat curing and dicing are performed to obtain hollow-structure packages. As such photosensitive resin compositions, there have been disclosed a photosensitive resin composition containing an acrylic resin, photopolymerizable compound and photopolymerization initiator (Patent Document 1: JP-A 2002-351070), a photosensitive resin composition containing a photosensitive, modified epoxy resin, photopolymerization initiator, diluting solvent and heat-curable compound (Patent Document 2: JP-A 2003-177528), and so on.
As a simple heat-curable adhesive, an adhesive dry film containing a polyimide resin, curable compound and silane coupling agent has been also disclosed (Patent Document 3: JP-A 2003-253220).